I had a Powerline connection to my Oppo 83 and it worked pretty well but was very expensive and didn't play well with surge protectors. I also used a wireless access point (Asus RT-N13) that worked pretty well to connect my TV, receiver and the Oppo for a while and this also worked well for music and video up to 720p.
The 83 wouldn't work with the 93/95 wireless dongle, and with my latest purchases having Wi-Fi built in the need for these add-on options just faded away.
Projector: Panasonic PT-AE7000
Screen: 120" Elite ezFrame Fixed Screen (CineWhite 1.1)
TV: Panasonic TH-P65ST50 PDP
Receiver: Onkyo TX-NR5009
Blu-ray: Oppo BDP-93
Freeview|HD: Vantage HD6000T PVR + Seagate Expansion 1TB HDD
Speakers : KEF Q900 Left/Right Front, KEF Q600c Centre, B&W DM601s2 Left/Right Surround, Mission 7DS/77DS Left/Right Back/Front Surrounds
Subwoofer : SVS SB13-Plus
Cables : AudioQuest, RapalloAV